JP2023539170A - Continuous blood pressure monitoring method and device - Google Patents

Abstract

The present invention is capable of: 1) being comfortable for the person when the person is conscious; 2) allowing the person to relax; 3) allowing the person to fall asleep; or 4) allowing the person to fall asleep already. To enable a person's blood pressure measurements to be obtained non-invasively in a repetitive manner and to provide frequent updates of blood pressure measurements while avoiding waking the person in case of an accident. After obtaining (304) a first set of blood flow waveform data associated with the blood pressure measurement, receiving (306) a second set of waveform data and identifying (308) a parameter change in the second waveform data; A correlation between this parameter change and a blood pressure measurement is calculated (310), a virtual blood pressure is generated (312), and an operation is performed based on the virtual blood pressure (314).

Description

The present invention relates to monitoring blood pressure.

Medical practices used to ask whether patients had a "pulse" when assessing their health status. But as drugs have gotten better, we now ask what a patient's blood pressure is; for just like a patient's heart rate, blood pressure determines whether a person is feeling well or not. This is because it is one of the earliest signs of change that can tell a health care provider that something is getting worse. That is, blood pressure is an important sign (or vital sign). Blood pressure is therefore referred to as a "vital" sign.

Because frequent blood pressure monitoring is necessary in so many situations, an "art line," or catheter that penetrates the skin, is placed, usually in the radial artery, to continuously obtain accurate blood pressure measurements. There are many things to do. Another way to do this, though less precise, is by a blood pressure cuff (measuring band) placed on the arm or leg. For near-continuous (eg, every 15 minutes) monitoring, the cuff goes through cycles of inflation and release to measure blood pressure.

Although ultimately tolerable, the intracarpal arterial line is uncomfortable/unnatural (negatively affecting the patient's comfort level, both awake and asleep). And a blood pressure cuff that inflates to 200 mmHg every 15 minutes is not something a person can ignore or sleep through unnoticed. Additionally, arterial lines can cause infections, arterial thrombosis, hand ischemia, and numerous other health problems. And blood pressure cuffs are a source of infectious disease transmission, are uncomfortable, and lead to sleep deprivation and long hospital stays. And while both of these devices/methods can obtain blood pressure, each poses significant costs to patients and society. Therefore, a need exists for continuous blood pressure monitoring without the uncomfortable repetitive cycling of invasive arterial lines or blood pressure cuffs.

BACKGROUND OF THE INVENTION Measuring blood pressure in a person (eg, a patient or subject) is a measurement of the pressure of a volume of a person's blood against the walls of the person's blood vessels (eg, the aorta). This pressure is created by the person's heart pumping that much blood into the blood vessels, and the blood vessels following suit. Blood pressure measurements are typically systolic blood pressure measurements (e.g., taken during a heartbeat) versus diastolic blood pressure measurements (e.g., the lowest pressure taken between two heartbeats) within a person's cardiac cycle. expressed in terms of maximum pressure measured). Blood pressure measurements are measured in millimeters (mmHg) of mercury sphygmomanometers above ambient atmospheric pressure (although aneroid or electronic devices do not actually contain mercury).

Blood pressure measurements – along with respiratory rate measurements, heart rate measurements, oxygen saturation measurements, and body temperature measurements – are used by health care professionals (e.g., doctors, nurses) to diagnose a person. It is one of the various vital signs of people who can. At rest, a person can have a blood pressure reading of about 120 millimeters of mercury sphygmomanometer systolic versus about 80 millimeters of mercury sphygmomanometer systolic, commonly expressed as "120/80 mm Hg."

Blood pressure measurements can be obtained non-invasively from a blood pressure monitor having an inflatable cuff and a display (eg, digital display, analog display) when the inflatable cuff is worn by a person (eg, on the upper arm). The inflatable cuff is inflated to a pressure above the highest expected for the person and then slowly deflated while detecting various pulses of pressure within the inflatable cuff to obtain systolic blood pressure measurements and dilation. Detect periodic blood pressure measurements. This method of non-invasively obtaining blood pressure measurements is commonly known as an oscillometric method, and the method can be repeated to provide a variety of frequent updates of blood pressure measurements. However, this high frequency of repetition (1) may be uncomfortable (painful) to the person when the person is conscious, (2) may interfere with the person's relaxation, and (3) may prevent the person from falling asleep. or (4) can wake a person up if the person is already asleep.

Skidmore R and Woodstock JP (1980), “Ultrasound in Machine & Biology”, V6, pp.7-10

There is a new medical term, "sleep hygiene," in which there is a targeted effort to check a patient's sleep while they are being cared for (in the hospital or at home). Sleep deprivation is clearly associated with additional tests and complications leading to prolonged hospitalization or repeat visits. One of the biggest causes of sleep deprivation is the blood pressure cuff. Broadly speaking, the present invention can (1) be comfortable for a person when the person is conscious, (2) allow the person to relax, (3) allow the person to fall asleep, or ( 4) Ability to take blood pressure measurements non-invasively in a repetitive manner to provide frequent updates of blood pressure measurements while avoiding waking the person if they are already asleep. Make it.

At least some of the engineering advantages described above include sensors configured to detect blood flow originating from a contracting human heart (e.g., ultrasound sensors, continuous wave sensors, ultrasound Doppler sensors, oxygen saturation sensors, etc.). can be obtained from a pulse oximeter (degree sensor - pulse oximeter). The sensor is carried by a wristband (or other wearable device) and placed on the upper or lower limbs, torso, head, wrists, fingers, toes, upper arms, etc. ) When worn, the sensor can detect blood flow and thereby generate a blood flow waveform that can be communicated to the processor. In response, the processor processes the waveform so that it can predict, anticipate, or estimate likely changes in the blood pressure (or heart rate) measurement (the processor may create a "virtual blood pressure" measurement). , generated from blood flow waveforms and baseline blood pressure measurements), and therefore, when an indication of a significant change in blood pressure (or heart rate) readings is detected, repeating the person's blood pressure (or heart rate) by means of the inflatable cuff alone. A measurement may be requested, the indication being to meet or not meet a preset (or predetermined) blood pressure (or heart rate) measurement threshold. Therefore, this method can significantly reduce the total number of cumbersome oscillometric blood pressure (or heart rate) measurements required from the person, and is therefore (1) comfortable for the person when the person is conscious; can (2) allow a person to relax, (3) allow a person to fall asleep, or (4) wake a person if the person has already fallen asleep. This can be avoided. This method then offers advantages in the management of hypertension. By providing a mechanism for continuous monitoring, hypertensive patients can have a clearer picture of how their lifestyle and medications affect their blood pressure and, if desired, Adjustments can be made accordingly. Additionally, this can provide one's physician with greater insight into which treatment options are likely to be most effective. These are features of treatment that are not fully available when patients do not have the ability for continuous monitoring of blood pressure.

In a preferred embodiment, the method includes: instructing, by the processor, a sensor worn by the subject to monitor a first blood flow of the subject during a period comprising a cardiac cycle of the subject; generating a first set of waveform data representative of a cardiac cycle during a period of time, the first set of waveform data being associated with a blood pressure measurement; receiving from the sensor a second set of waveform data in the second blood flow; identifying, by the processor, a parameter change in the second set of waveform data relative to the first set of waveform data; , calculating a correlation between the parameter change and the blood pressure measurement, thereby generating a virtual blood pressure (a calculated value based on the blood pressure measurement and the parameters of the waveform data set) for the second blood flow; and performing an operation based on the virtual blood pressure.

In a preferred embodiment, the apparatus comprises: a processor, the processor: instructing a sensor worn by the subject to monitor a first blood flow in the subject during a period including a cardiac cycle of the subject; a sensor generates a first set of waveform data representative of a cardiac cycle during the period; the first set of waveform data is related to a blood pressure measurement; after the first set of waveform data is generated by the sensor; receiving a second set of waveform data in a second blood flow from the sensor; identifying a parameter change in the second set of waveform data relative to the first set of waveform data; calculating a correlation between the parameter change and the blood pressure measurement; This generates a virtual blood pressure for the second blood flow (a calculated value based on the parameters of the blood pressure measurement and the waveform data set); and is programmed to perform operations based on the virtual blood pressure.

1 is a schematic diagram of an embodiment of a processor in communication with a memory, a sensor, and a blood pressure monitor in accordance with various principles of the present invention. FIG. 2 is a three-dimensional view of an embodiment of the apparatus configured to measure blood pressure of a patient according to FIG. 1 in accordance with various principles of the present invention; FIG. 3 is a flowchart of an embodiment of a process for generating virtual blood pressure (or heart rate) according to FIGS. 1-2 in accordance with various principles of the present invention; FIG. 4A and 4B are waveform diagrams of exemplary blood flow waveforms according to FIGS. 1-3 in accordance with various principles of the present invention; FIG. FIG. 2 is a schematic block diagram of the peripheral vasculature. 6 is a diagram showing an electrical circuit equivalent to the schematic diagram of FIG. 5. FIG. FIG. 3 is a diagram showing acceleration during systole. FIG. 3 shows a series of waveforms with different time compression ratios (compressed, normal, and expanded). FIG. 7 is a diagram showing a linear relationship between specific patient parameters used in the second embodiment. FIG. 7 is a diagram illustrating a monitoring process using a linear relationship of patient-specific parameters according to a second embodiment; FIG. 3 is another view of the device for measuring blood pressure of a patient.

In general, the present invention can be used to (1) be comfortable for a person while conscious, (2) allow a person to relax, (3) allow a person to fall asleep, or (4) ) allows blood pressure readings to be taken in a non-invasive manner in a repetitive manner to provide frequent updates of blood pressure readings while avoiding waking the person if they are already asleep. do. For example, at least some of these engineering advantages may be associated with devices such as, but not limited to, smart phones, smart watches, tablet devices, smart wristbands, etc. that are configured to detect blood flow in a person. (e.g. ultrasonic sensor, continuous wave sensor, ultrasonic Doppler sensor, oxygen saturation sensor - pulse oximeter, e.g. for obtaining a photo (or digital) plethysmogram) photometric sensor). A digital (or photo) plethysmogram is an optically detected blood volume change in the microvascular bed of a tissue. When the sensor is carried by a wristband (or other wearable device) and worn by a person, the sensor can detect blood flow, thereby generating a blood flow waveform, and communicating this waveform to the processor. . In response, the processor processes the waveforms so that virtual blood pressure (or heart rate) and likely changes in blood pressure (or heart rate) measurements can be predicted, anticipated, or estimated, and thus: Repeated measurements of a person's blood pressure (or heart rate) with an inflatable cuff only can be requested when an indication of a significant change in blood pressure (or heart rate) reading is detected; or meeting or failing to meet a predetermined) blood pressure (or heart rate) measurement threshold. Therefore, this method can significantly reduce the total number of blood pressure (or heart rate) measurements required from a person, and thus can (1) be comfortable for the person when he or she is conscious; , (2) may allow the person to relax, (3) may allow the person to fall asleep, or (4) avoid waking the person if the person has already fallen asleep. be able to.

The invention will now be described more fully with reference to FIGS. 1-4, in which several embodiments of the invention are shown. However, this invention may be embodied in many different forms and should not necessarily be considered as limited to the embodiments disclosed herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the various concepts of the invention to those skilled in the art.

The various terms used herein may imply direct or indirect, total or partial, temporary or permanent, action or inaction. For example, when an element is referred to as being ``on'', ``connected to'', or ``coupled with'' another element, it is assumed that the element is There may be intervening elements that are present directly, directly connected to other elements, can be directly coupled to other elements, or include indirect or direct variants. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present.

As used herein, the various singular forms "a," "the," and "the" refer to various plural forms (e.g., two, three, four, etc.), unless the specific context clearly dictates otherwise. , five, six, seven, eight, nine, ten, tens, hundreds, thousands).

As used herein, the various verbs "comprising," "comprising," or "comprising," "including" refer to the features, integers, or steps described. , act, element, or component, but does not exclude the presence or addition of one or more other features, integers, steps, acts, elements, or components, or groups thereof.

As used herein, "or" is intended to mean an inclusive or rather than an exclusive or. That is, unless otherwise specified or clear from context, "X uses A or B" is intended to mean any of the natural inclusive set of permutations. That is, when X uses A; when X uses B, or when X uses A and B together, "X uses A or B" is satisfied under any of the above cases.

As used herein, the term "or other," "combination," "combination," or "combination thereof" refers to all permutations and combinations of the items listed preceding the term. For example, "A, B, C, or a combination thereof" is intended to include at least one of A, B, C, AB, AC, BC, or ABC, where the order is important in the particular context. In some cases, it is intended to include at least one of BA, CA, CB, CBA, BCA, ACB, BAC, or even CAB. Continuing with the example, combinations involving repetitions of one or more items or words are expressly included, such as BB, AAA, AB, BBC, AAAABCCCC, CBBAAA, CABABB, etc. In general, those skilled in the art will understand that there is no limit to the number of items or words in any combination unless the context clearly dictates otherwise.

All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Various terms, such as those defined in commonly used dictionaries, unless explicitly defined herein, should be construed to have meanings consistent with their meanings in the context of the relevant art. It should not be interpreted in an ideal or overly formal sense.

As used herein, relative terms such as "lower," "lower," "upper," and "upper" are used herein as illustrated in the accompanying set of illustrative drawings. It can be used to describe the relationship between one element and another element. These relative terms are intended to encompass different arrangements of the illustrated technology in addition to those depicted in the accompanying set of illustrative figures. For example, if an apparatus in the accompanying drawing set were to be turned upside down, various elements depicted as being "below" other elements would be "above" other elements. placed on the side. Similarly, if an apparatus in one of the illustrative drawings were to be turned upside down, various elements described as being "beneath" or "beneath" other elements would be Placed "above" other elements. Thus, various examples of the term "lower" or "lower" can encompass both upper and lower configurations.

"About" or "approximately" as used herein refers to a variation of +/-10% from the nominal value/term. Such variations are always included in any given value/term provided herein, whether or not specifically referenced.

Features described with respect to particular embodiments may be incorporated into or combined with some of the various embodiments in any permutation or combination. Different aspects or elements disclosed herein can be combined in a similar manner.

As used herein, the terms first and second are used to describe various elements, components, regions, layers, or sections; or classification should not necessarily be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Accordingly, a first element, component, region, layer, or section described below may be referred to as a second element, component, region, layer, or section without departing from the various teachings of this disclosure. can be called.

Features described with respect to a particular embodiment may be incorporated into and subcombined into, or combined with, or subcombined with, various other embodiments. Also, different aspects or elements of the embodiments described herein may be combined or subcombined in a similar manner. Furthermore, some embodiments, individually or collectively, may be components of a larger system, in which other procedures may take precedence over the application of these embodiments or otherwise The application of these embodiments can be modified. Additionally, multiple steps may be required before, after, or concurrently with the embodiments disclosed herein. It is noted that at least any or all of the methods or processes disclosed herein can be performed, at least in part, by at least one entity in any number of ways.

Embodiments of the invention are described herein with reference to illustrations of idealized embodiments (and intermediate structures) of the invention. As such, variations from the various shapes shown, for example as a result of manufacturing techniques or manufacturing tolerances, are to be expected. Accordingly, the various embodiments of the invention should not be construed as necessarily limited to the various specific shapes of the regions illustrated herein, but are intended to include deviations in shape resulting from, for example, manufacturing. Become.

Any or all elements disclosed herein may be unitary, formed from structurally continuous identical elements, or may be an assembly or module. so that they can be manufactured separately or connected. Any or all of the elements disclosed herein can be manufactured by any manufacturing process, whether additive, subtractive, or any other type of manufacturing method. For example, some manufacturing processes include three-dimensional (3D) printing, laser cutting, computer numerically controlled routing, milling, pressing, stamping, vacuum forming, Includes hydroforming, injection molding, lithography, etc.

FIG. 1 shows a schematic diagram of an embodiment including a processor in communication with a memory, a sensor, and a blood pressure monitor, in accordance with various principles of the invention. Specifically, system 100 includes a processor 102, a memory 104, a blood flow sensor 106, and a blood pressure monitor 108. System 100 can be battery powered (eg, rechargeable batteries, lithium ion batteries, disposable (primary) batteries). However, system 100 can be powered (eg, via a power cord or data cable plugged into a suitable power source).

The processor 102 can be a processing circuit, a digital circuit, an integrated circuit, an application-specific integrated circuit, an application-specific integrated processor, a microprocessor, a single-core processor, a multi-core processor, a graphics processing unit (image processing device), a physics processor, or a processor. including a processing unit, digital signal processor, coprocessor, network processor, front end processor, field programmable gate array, programmable logic controller, system on a chip, or other form of processing logic . Processor 102 communicates (e.g., wired, wireless, waveguide) with memory 104, blood flow sensor 106, and blood pressure monitor 108, such that processor 102 communicates with memory 104, blood flow sensor 106, and blood pressure monitor 108. They can be controlled by sending data to and receiving data from them. Note that the blood flow sensor 106 or the blood pressure monitor 108 can include the processor 102. The processor 102 can be used for hats, helmets, earphones, hearing aids, headphones, eyeglass frames, contact lenses, bands, clothing, shoes, jewelry, medical devices, activity trackers, hand cuffs, wristbands, smartphones, and tablets. Terminals, laptop computers, desktop computers, vehicles, implants, hats, rimless hats, skullcaps, headbands, jackets, shirts, ties, belts, bands, shorts (seat pants, shorts), pants , socks, undershirts, underwear, bras, jerseys, skirts, dresses, blouses, sweaters, scarves, gloves, bandanas, elbow pads, knee pads, pajamas, robes, shoes, dresses included in, physically affixed to, electrically connected to, as a component of, or as a component of, at least one of a shoe, sneaker, boot, or heeled shoe; At least one of the following is possible:

Memory 104 includes non-transitory media configured to store data for use by processor 102. A processor can read, write, modify, or erase this data. For example, memory 104 may store a set of instructions executable by processor 102 to perform various techniques disclosed herein.

The blood flow sensor 106 is configured to come into contact with a person, and even when placed on the human integument surface (e.g., upper and lower limbs, torso, head, wrist, fingers, toes, upper arm), It may be placed over an overlying material (eg, a bandage, gauze pad, clothing). For example, blood flow sensor 106 can be worn by a person as a wristband. For example, the blood flow sensor 106 may be an ultrasonic sensor, an ultrasonic Doppler sensor, a sealed Doppler probe, etc. on such devices, such as, but not limited to, smart phones, smart watches, tablet devices, smart wristbands, etc. , continuous wave sensors, continuous wave ultrasound Doppler blood flow sensors, oxygen saturation sensors - pulse oximeters, or with others (such as photometric sensors (e.g. for obtaining photo (or digital) plethysmograms)). can do. For example, blood flow sensor 106 can be a commercially available BlueDop® probe. When blood flow sensor 106 contacts (or nearly contacts) a person, blood flow sensor 106 detects blood flow in the person and responsively generates a set of data representative of the blood flow. This set of data can be plotted and visualized (eg, with an oscilloscope) as a waveform of blood flow (eg, blood displacement as a function of time). For example, this set of data can be plotted on a scale where the X-axis corresponds to time interval (or distance) and the Y-axis corresponds to blood displacement. For example, this set of data can be plotted as well as plotting force or work over a distance. The movement of blood through blood vessels is work in the classical sense - force over a distance. Measures blood pressure based on area under the curve (of force over a distance), or work done. Work is force over a distance, and force is mass times acceleration. A blood flow waveform (eg, a Doppler waveform) is a force curve due to the sum of the forward motion of the mass (blood) and the backward motion of the mass; this waveform is the force curve of the blood. Blood pressure is the slope of the waveform from moment to moment, the amplitude represents the mass (blood volume), and the distance is the visible spectrum of, for example, a Doppler probe. Therefore, the amount of work is the sum of the areas under the waveform. Now, knowing the diameter of the tube or blood vessel, the pressure can be calculated based on the Bernoulli equation. However, by using the area under the curve and calculating the correlation between this area and baseline blood pressure, changes in the area under the curve can be tracked to calculate a digital (ie, virtual) blood pressure. This can be applied to any waveform representative of blood flow, ie, pulse oximeter waveform, plethysmograph, Doppler, etc. However, historically, taking advantage of this fact has allowed the body to change the diameter of the tube (artery), the stiffness of the tube (artery) (conservation of energy), and the followability (compliance) of the vascular bed in outflow. This was difficult due to factors such as: For at least these reasons, trying to calculate a correlation between heart rate and blood pressure gives very inaccurate results. Alternatively, attempting to calculate the correlation between only the amplitude of the waveform and blood pressure is accurate for only one point in space, and calculating the correlation with blood pressure taken at the same time in the body to determine the diameter, stiffness, and Changes in outflow resistance must be compensated for. The inventors have recognized that the work of blood moving, the area under the waveform, can be used as a tool to estimate (calculate) relaxation of blood pressure. The slope of the waveform, the duration of the waveform peak, and other parameters are influenced by the tube diameter, stiffness, and outflow resistance. By considering the characteristics of these parameters, the work of moving blood can be determined, which allows, after an initial calibration of the measurements, to continuously track blood pressure over extended periods of time.

The blood flow sensor 106 functions as a waveform generator to form a blood flow waveform as the set of data, and outputs the set of data either continuously or periodically as requested by the processor 102. and (eg, by wire, wireless, waveguide) to processor 102 .

Blood pressure monitor 108 includes a wearable cuff (e.g., wrist cuff, upper arm cuff), a bladder (air bladder), a pump (e.g., gas pump, air pump), a valve (e.g., solenoid valve, gas valve, air valve), a sensor (e.g., pressure sensors, transducers), and a controller, which may be a processor 102 or other processing device. The controller communicates (e.g., wired, wireless, waveguide) with the pumps, valves, and sensors, such that the controller can send data to and receive data from the pumps, valves, and sensors. can be controlled by The wearable cuff includes a bladder. The valve can be included within the wearable cuff or removed from the wearable cuff. In response to commands by the controller, the pump is configured to expel gas (e.g., a volume of air) into the bladder to inflate the wearable cuff while the wearable cuff is being worn by the person. . The pump can also be inflated with fluid. In response to commands by the controller, the valve is configured to vent gas/fluid from the bladder, thereby causing the bladder to deflate while the wearable cuff is worn by the person. The sensor is configured to determine a systolic blood pressure measurement of the person and a diastolic blood pressure measurement of the person while the bladder is deflated by the valve in response to commands by the controller. The sensor transmits systolic and diastolic blood pressure measurements (eg, by wire, wireless, waveguide) to the controller.

Note that the blood pressure monitor 108 can include an amplifier and an analog-to-digital converter (ADC). Thus, the sensor can generate an analog signal (eg, a pressure reading) while the wearable cuff is worn by a person. The sensor can send an analog signal to an amplifier for amplification. The amplifier sends the amplified analog signal to the ADC, which converts the signal to a digital signal. The ADC can send digital signals to a controller that performs various partial processes to determine a person's systolic blood pressure measurement and a person's diastolic blood pressure measurement, and these measurements are It can be accompanied by a person's pulse.

Blood pressure monitor 108 may include at least one of processor 102, memory 104, or blood flow sensor 106. For example, blood pressure monitor 108 may include a housing containing processor 102 and memory 104, whereas blood flow sensor 106 is worn by a person outside of the housing. For example, the wearable cuff can include the blood flow sensor 106, or the wearable cuff can exclude the blood flow sensor 106 (e.g., the wearable cuff can be worn on the upper arm of a person and The sensor 106 can be included in a wristband worn on a person's wrist, and vice versa, or on a finger cuff worn on a finger or finger). However, the blood flow sensor 106 can be incorporated in other ways or worn non-invasively by a person within other areas (e.g., upper and lower extremities, head, torso, fingers, toes, upper arms). Can be done. In some implementations, the blood pressure monitor 108 is omitted and the processor 102 transmits the person's systolic blood pressure measurements and the person's diastolic blood pressure measurements to a wearable device (e.g., an activity tracker, a wristband activity tracker, (smartwatch, smart phone), and the wearable device itself can obtain a person's diastolic blood pressure measurement and a person's systolic blood pressure measurement when the wearable device is worn by the person; may receive a person's diastolic blood pressure readings and a person's systolic blood pressure readings from other devices worn by the person or as manual input by the person or the person's caregiver (e.g., doctor, nurse, parent). Blood pressure measurements may be received. Note that a person's diastolic blood pressure measurement can be calculated, estimated, or predicted from a systolic blood pressure measurement, or manually entered by the person or the person's caregiver (e.g., doctor, nurse, parent). can do.

In one mode of operation, transmitting (by wire, wireless, waveguide) a first blood pressure measurement of a person at a first instant (e.g., a first systolic blood pressure measurement and a first diastolic blood pressure measurement) to the processor 102 The processor 102 can be programmed to request the blood pressure monitor 108 (or other device) to do the following: Similarly, processor 102 can be programmed to request blood flow sensor 106 to transmit (by wire, wireless, waveguide) a set of data to processor 102, where the set of data is Regardless of where a person wears the wearable cuff, or whether it is attached to another part of the person, the blood flow sensor 106 may be detected before, during, or after the blood pressure monitor 108 obtains the first blood pressure measurement. Generated by blood flow sensor 106 based on monitoring the person's blood flow, whether continuously or periodically. To this end, processor 102 is programmed to continuously analyze a set of data (forming a waveform) received from blood flow sensor 106 to determine whether a change in waveform shape exists. The change in waveform shape is indicative of a significant change in the person's blood pressure and is determined based on whether a preset or predetermined threshold is met or not. Accordingly, based on the processor 102 determining that there is a change in waveform shape indicative of a significant change in the person's blood pressure, the person's second blood pressure measurement at a second instant after the first instant (e.g., The processor 102 can be programmed to request the blood pressure monitor 108 to transmit (by wire, wireless, waveguide) a second systolic blood pressure measurement and a second diastolic blood pressure measurement to the processor 102. . The second blood pressure measurement may be different than the first blood pressure measurement. The existence of a change in waveform shape may be based on meeting or not meeting a preset or predetermined threshold, or based on a preset or predetermined time since the first blood pressure measurement (e.g. , approximately 4-8 hours, but each of these limits can vary).

FIG. 2 shows a three-dimensional view of an embodiment of an apparatus configured to measure a patient's blood pressure according to FIG. 1 in accordance with various principles of the present invention. Specifically, system 200 includes a housing 202, a tube (eg, hose) 204, a blood pressure cuff 206, a data line 208, and a blood flow sensor 210 (eg, a Doppler blood flow sensor). The blood pressure cuff is worn on the upper arm 214 of a person's arm 212. Blood flow sensor 210 is worn on wrist 216 of arm 212 .

Blood pressure monitor 108 includes a housing 202, a tube 204, a blood pressure cuff 206, a processor 102, and a memory 104, as described above. The housing 202 includes a pump of the blood pressure monitor 108, a valve of the blood pressure monitor 108, and a sensor of the blood pressure monitor 108. In some implementations, housing 202 can include an amplifier and an analog-to-digital converter (ADC). Tube 204 spans between blood pressure cuff 206 and housing 202 such that the pump, in response to commands by the controller, connects blood pressure cuff 206 (e.g., a bladder) with gas (e.g., , a large volume of air) or a fluid, and the controller can include a processor 102 . The valve may direct gas/fluid out of the blood pressure cuff 206 thereby deflating the blood pressure cuff 206 in response to commands by the controller, which may include the processor 102. The sensors in the housing 202 can send their readings to a controller, which can be the processor 102, so that the controller can transmit the person's systolic blood pressure measurements and the person's diastolic blood pressure measurements. Alternatively, the sensor itself may measure the person's systolic blood pressure reading and the person's diastolic blood pressure reading and send the person's systolic blood pressure reading and the person's diastolic blood pressure reading to the controller. do.

A data line 208 (e.g., data cable, fiber optic cable) spans between the blood flow sensor 210 and the housing 202 so that the blood flow sensor 210 transmits its data over the data line 208 to the controller. (or vice versa), and the controller can be processor 102 . In some embodiments, there is no data line 208, and each of the housing 202 and blood flow sensor 210 includes a wireless network interface (e.g., a wireless receiver, a wireless transmitter, a wireless transceiver), allows the respective network interfaces to communicate with each other. For example, processor 102 can communicate with a wireless network interface of housing 202 to transmit data to and receive data from the wireless network interface. To this end, blood flow sensor 210 (or other suitable sensor configured to detect blood flow originating from a contracting human heart as disclosed herein) transmits its data to The data may be transmitted to housing 202 through a wireless network interface, which transmits this data to a controller, which may be processor 102 . In some implementations, blood flow sensor 210 is included within blood pressure cuff 206. To this end, the tube 204 may include a data line 208, either internal or external, or the data line 208 may be omitted and the blood flow sensor 210 or blood pressure cuff 206 may include a wireless network interface and be connected to the housing. can communicate with a wireless network interface of body 202;

Although housing 202 encloses processor 102, housing 202 is not worn by a person and is separate from and distinct from each of blood pressure cuff 206 and blood flow sensor 210. However, this configuration can be varied. For example, blood pressure cuff 206 can include housing 202 or blood flow sensor 210. Similarly, blood flow sensor 210 can include housing 202 or blood pressure cuff 206. Similarly, housing 202 can include a blood flow sensor 210. Further, the processor 102 is capable of wireless communication with the blood flow sensor 210, but can communicate with the blood flow sensor 210 by wire and/or by waveguide. Note that the housing 202 includes a display (for example, a digital display or an analog display). However, the housing 202 can also avoid a display.

In one mode of operation, blood pressure cuff 206 is worn on the upper arm 214 and blood flow sensor 210 is worn on the wrist. Processor 102 within housing 202 may be programmed to request the pump within housing 202 to deflate blood pressure cuff 206 through tube 204 during this time. Based on such inflation of blood pressure cuff 206 and deflation of blood pressure cuff 206 , a sensor within housing 202 generates a first set of blood pressure readings on upper arm 214 and sends the first set of blood pressure readings to processor 102 . transmitting, thereby causing processor 102 to determine a first blood pressure measurement (e.g., a first systolic blood pressure measurement and a first diastolic blood pressure measurement) of the person at a first instant in time based on the first set of readings. generate. Similarly, processor 102 can be programmed to request blood flow sensor 210 to send a set of data (forming a waveform) to processor 102 over data line 208, where the set of data is , the blood flow sensor 210 monitors the blood flow of the person, whether continuously or periodically, before, during, or after the processor 102 obtains the first blood pressure measurement. is generated. To this end, processor 102 may be programmed to continuously analyze a set of data (forming a waveform) received from blood flow sensor 210 and determine whether a change in waveform shape exists. The change in waveform shape is indicative of a significant change in the person's blood pressure and is determined based on whether a preset or predetermined threshold is met or not. Accordingly, in response to the processor 102 determining that there is a change in waveform shape indicative of a significant change in the person's blood pressure, the blood pressure cuff 206 is inflated through the tube 204 and valve within the housing 202. The processor 102 can be programmed to request the pump within the housing 202 to deflate the blood pressure cuff 206 through the blood pressure cuff 204, and the presence of a change in waveform shape is determined by a preset or predetermined Based on whether a threshold is met or not, or a preset or predetermined condition, such as a period of time (e.g., about 4 to 8 hours, but each of these limits since the first blood pressure measurement) (can be changed) has elapsed. Based on these inflation of blood pressure cuff 206 and deflation of blood pressure cuff 206 , a sensor within housing 202 generates a second set of blood pressure readings on upper arm 214 and sends the second set of blood pressure readings to processor 102 . transmitting, thereby causing processor 102 to determine, based on the second set of readings, a second blood pressure measurement of the person at a second instant after the first instant (e.g., a second systolic blood pressure measurement and a second diastolic blood pressure measurement). blood pressure measurements). The second blood pressure measurement may be different than the first blood pressure measurement.

FIG. 3 depicts a flowchart of an embodiment of a process for generating virtual blood pressure (or heart rate) according to FIGS. (based on the parameters of the above set of waveform data). Specifically, process 300 includes a set of blocks 302-314 performed by system 100 of FIG. 1 or system 200 of FIG.

At block 302, processor 102 obtains blood pressure measurements (eg, systolic blood pressure measurements and diastolic blood pressure measurements) for a person. Processor 102 forms a blood pressure measurement from a set of readings received from a sensor contained within housing 202 of blood pressure monitor 108 . Alternatively, processor 102 may receive blood pressure measurements from a sensor contained within housing 202 of blood pressure monitor 108 . Alternatively, the processor 102 can receive blood pressure measurements from other devices (e.g., activity trackers, smart watches, smart phones) that may themselves measure blood pressure measurements when the wearable device is worn by a person. Measurements may be taken or blood pressure measurements may be received from other devices worn by the person or by the person or the person's caregiver (e.g., doctor, nurse, guardian). Blood pressure readings can be received as manual input by.

At block 304, the processor 102 receives a first set of waveform data (e.g., wired, wireless, guided wave path). This means that processor 102 may detect a sensor worn by a person for a period of time that includes a cardiac cycle (e.g., approximately 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 seconds, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 minutes (less than, equal to, or longer than these times), so that the sensor A first set of waveform data representative of a cardiac cycle can be generated. The first set of waveform data relates to blood pressure measurements. For example, blood pressure measurements may be obtained before, during, or after the sensor generates the first set of data. When a person has a head, torso, upper and lower limbs, wrists, hands, fingers, ankles, toes, or thighs, the sensor It can be worn on the hands, fingers, ankles, toes, or thighs. However, the blood pressure monitoring device (e.g., blood pressure cuff 108) can include a blood pressure cuff 206 worn by a person (e.g., on the upper arm 214, wrist 216), and the blood pressure cuff 206 (e.g., by inflation and deflation thereof) To enable blood pressure measurements, blood pressure cuff 206 can include sensors, either internal or external.

At block 306, after the sensor generates the first set of waveform data, the processor 102 receives (by wire, wireless, waveguide) a second set of waveform data for a second blood flow from the sensor.

At block 308, processor 102 identifies parameter changes in the second set of waveform data relative to the first set of waveform data. This means that the processor 102 reads the first set of waveform data and the second set of waveform data, and compares the second set of waveform data with the first set of waveform data (e.g., based on values at a particular point in time). This can be generated by identifying differences in the second set of waveform data relative to the first set of waveform data, which differences provide information on parameter changes. For example, the difference can be based on a value at a particular point in time, or a range of values for a range of points in time. For example, the processor 102 may derive a first parameter of the first waveform shape in the first set of waveform data for each cardiac cycle during the first blood flow period, and for each cardiac cycle during the second blood flow period. , deriving a second parameter of a second waveform shape in the second set of waveform data, and being programmed to identify a parameter change based on identifying a change between the first parameter and the second parameter. Can be done. For example, each of the first parameter and the second parameter is a heartbeat cycle. For example, each of the first and second parameters is an initial rise height, discussed further below. For example, each of the first and second parameters is a period of initial rise, discussed further below. For example, each of the first parameter and the second parameter is a frequency of a vibrational component as further described below.

At block 310, processor 102 calculates a correlation between parameter changes and blood pressure measurements as described further below. For example, a parameter change can be a change in waveform shape.

At block 312, the processor 102 generates a virtual blood pressure (or heart rate) for the second blood flow (a calculated value based on the blood pressure measurements and parameters of the waveform data set), as described further below.

At block 314, processor 102 performs an operation based on the virtual blood pressure (or heart rate). For example, this operation can include instructing a blood pressure monitoring device (e.g., a blood pressure monitor) to obtain other blood pressure measurements that are different from the blood pressure measurements associated with the first set of waveform data. . Note that the blood pressure measurement value associated with the first set of waveform data can also be acquired by this blood pressure monitoring device. For example, the operations described above may include requesting, directing, retrieving, receiving, generating, inputting, facilitating, or accepting input from an input device (e.g., a touch screen, a microphone, This input may include user input, whether from the person wearing the sensor or their caregiver. For example, the operations described above may include requesting, directing, retrieving, receiving, transmitting, generating, outputting, facilitating, or receiving output from an output device (e.g., display , speakers, sensors, motors, pumps, valves), and this output may include output to the user, whether to the person wearing the sensor or to their caregiver. can. For example, the above operation may include the processor 102 determining whether the virtual blood pressure (or heart rate) is within a predetermined range or a certain percentage thereof with respect to the actually obtained blood pressure of the person. Can be done. Within a predetermined range, or a certain percentage thereof, there is no need to generate a new calibration (eg, blood flow sensor 106, Doppler blood flow sensor 210, continuous wave sensor). However, if it is outside the predetermined range, or a certain percentage thereof, recalibration (eg, blood flow sensor 106, Doppler blood flow sensor 210, continuous wave sensor) will occur. For example, as disclosed herein, the operations may include outputting or transmitting a virtual blood pressure or a virtual heartbeat, respectively, through an output device (e.g., display, speaker) or (e.g., wired, wireless, waveguide). ) may include instructing the transmitter.

In one mode of operation, as disclosed herein, the person may be at rest and the processor 102 inflates and then deflates the blood pressure cuff 206 worn by the person. The first blood pressure (or heart rate) measurement can be programmed to generate a first blood pressure (or heart rate) measurement based on a first set of readings from a pressure sensor (eg, housed within housing 202). In some implementations, the first blood pressure (or heart rate) measurement is manually entered into the processor 102 (e.g., via a touch screen, cursor device, microphone, or other suitable input device) or otherwise or obtain a photo (or digital) plethysmogram (e.g., on an instrument such as, but not limited to, a smart phone, smart watch, tablet, smart wristband, etc.) from other devices (e.g., activity trackers, finger clips, wristband activity trackers, smart watches, blood pressure monitors, photometric sensors), and these devices themselves Blood pressure (or heart rate) can be obtained when a person is wearing a wearable device, or from other equipment the person is wearing, or from the person or that person's caregiver (e.g., a doctor, nurse, Blood pressure (or heart rate) measurements may be received as manual input by a parent or guardian.

A first time period that includes the first cardiac cycle (e.g., less than about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, tens, hundreds, thousands of seconds, minutes, or hours) is worn by the person (e.g., on the wrist 216) to monitor the person's first blood flow in real time during a period of time equal to or longer than , including any total or partial intermediate values. The processor 102 can be programmed to instruct a sensor (e.g., continuous wave sensor, Doppler blood flow sensor 210) to cause the sensor to detect a first set of signals representing a first cardiac cycle during a first time period. Generate readings. The first set of readings is associated with a first blood pressure (or heart rate) measurement, and each reading in the first set of readings includes a first data value and a first time value. For example, the first blood pressure (or heart rate) measurement can be a value before, during, or after the sensor generates the first set of readings, and vice versa. The first set of readings may be taken before the first blood pressure (or heart rate) measurement. For example, the first set of readings may be determined by processor 102 measuring a first blood pressure (or heart rate) measurement or receiving a first blood pressure (or heart rate) measurement from another device (e.g., a blood pressure sensor, a wearable). The first blood pressure (or heart rate) measurement may be taken within a predetermined period of time immediately before the first blood pressure (or heart rate) measurement. For example, the designated period of time can be about one hour or less or more. However, the first set of readings can be taken simultaneously with the first blood pressure (or heart rate) measurement, or can be taken after the first blood pressure (or heart rate) measurement.

a second period of time that includes the second cardiac cycle (e.g., less than about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, tens, hundreds, thousands of seconds, minutes, or hours); to instruct a sensor worn by the person to monitor the person's second blood flow in real time during a period of time equal to or longer than (including any total or partial intermediate value); Processor 102 can be programmed such that the sensor generates a second set of readings representative of a second cardiac cycle during a second time period. The first time period may or may not overlap with the second time period, and may or may not be the same as the second time period. Each reading in the second set of readings includes a second data value and a second time value, and the second time period begins after the first time period begins. The first period and the second period may overlap with each other, or may avoid overlapping with each other. The second period can be continuous with the first period, or there can be a third period intervening between the first period and the second period. The first cardiac cycle and the second cardiac cycle can be the same cardiac cycle or different cardiac cycles.

programming the processor 102 to add the first set of readings and the second set of readings to a data structure (e.g., a two-dimensional data structure, a three-dimensional data structure, a multi-dimensional data structure, an array, a vector); a first set of readings, whereby a first blood flow waveform corresponding to the first set of readings can be plotted based on the first data value and the first time value; A second blood flow waveform in which the set of readings corresponds to a second set of readings can be plotted based on the second data value and the second time value. As disclosed herein, when a sensor (e.g., a continuous wave sensor) contacts (or comes close to contacting) a person or a person wears a sensor, a first set of readings and a second set of readings are obtained. Processor 102 can be programmed to add readings to the data structure.

Deriving a first set of parameters from a first set of readings including a first data value and a first time value, and a second set of parameters including a second data value and a second time value, as disclosed herein. Processor 102 can be programmed to derive a second set of parameters from the set of readings. performing a comparison between the first set of parameters and the second set of parameters, and determining whether the second set of parameters indicates a predetermined change in the second blood flow waveform with respect to the first blood flow waveform based on the comparison; The processor 102 can be programmed to determine whether the predetermined change is indicative of a change in the first blood pressure measurement. For example, this change in value may be a blood pressure (or heart rate) measurement higher or lower than the last measurement. For example, the change in value or the predetermined change may or may not satisfy a predetermined threshold. As disclosed herein, when the sensor contacts or is worn by a person, a first set of parameters is derived from a first set of readings including a first data value and a first time value. Processor 102 can be programmed to do so. As disclosed herein, when the sensor contacts or is worn by a person, a second set of parameters is derived from a second set of readings including a second data value and a second time value. Processor 102 can be programmed to do so. The processor 102 is programmed to perform a comparison between the first set of parameters and the second set of parameters when the sensor contacts or is worn by a person, as disclosed herein. be able to.

As disclosed herein, when a blood pressure cuff 206 worn by a person is inflated and then deflated, a second set of readings from a blood pressure sensor (e.g., housed within housing 202) is obtained. Processor 102 can be programmed to generate a second blood pressure measurement based on the value. Once the first blood pressure (or heart rate) measurement is generated, processor 102 determines whether the predetermined change satisfies a predetermined threshold for the person or the time at which the first blood pressure (or heart rate) measurement was generated. (e.g., approximately 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, generating a second blood pressure (or heart rate) measurement based on at least one of: 4, 3, 2, or 1 hour or less (including any total or fractional values) elapsed; The blood pressure (or heart rate) measurement is after the first blood pressure (or heart rate) measurement. Processor 102 may be programmed to derive the first set of parameters or the second set of parameters based on the mathematical function or the result of the mathematical function. For example, the mathematical function can be a mean value function, median function, mode function, or other mathematical function. Note that each mode of derivation can be the same or non-identical in the sense of a mathematical function. As disclosed herein, when the continuous wave sensor contacts or is worn by a person, the second set of parameters determines a predetermined change in the second blood flow waveform relative to the first blood flow waveform. The processor 102 can be programmed to determine whether the . As disclosed herein, when blood pressure cuff 206 is worn by a person and the sensor contacts or is worn by the person, it generates a second blood pressure (or heart rate) measurement or generates a second blood pressure (or heart rate) measurement. Processor 102 can be programmed to receive blood pressure (or heart rate) measurements from a blood pressure sensor (or other device).

When a person has an arm 212, the blood pressure cuff 206 and sensor can be worn on the arm 212 (eg, on the wrist 216 or a finger, on the upper arm 214, or both). However, these configurations can vary. For example, a person can connect a first body part (e.g., head, torso, upper or lower extremities, arm 212, upper arm 214, wrist 216, finger, toe, thigh, ankle, leg, or any part thereof) and a second body part ( for example, the head, torso, extremities, arms 212, upper arms 214, wrists 216, fingers, toes, thighs, ankles, legs, or any portion thereof), and the blood pressure cuff is attached to the first body part; The sensor can be worn on the second body part, which can be the same body part or a different body part. In other examples, blood pressure cuff 206 can include a sensor.

As described further below, the first blood flow waveform has a first shape when displayed (e.g., by an oscilloscope), and the second blood flow waveform has a second shape when displayed (e.g., by an oscilloscope). has. For this reason, whether or not the second set of parameters indicates a predetermined change in the second blood flow waveform with respect to the first blood flow waveform is determined based on a comparison including a shape change between the first shape and the second shape. The processor 102 can be programmed to determine that the shape change corresponds to a change in value in the first blood pressure (or heart rate) measurement. The first set of parameters can include a first parameter corresponding to a first period of a first cardiac cycle, and the second set of parameters can include a second parameter corresponding to a second period of a second cardiac cycle. The first shape may correspond to a first time period and the second shape may correspond to a second time period. The first set of parameters can include a first parameter corresponding to a first height value of the first initial rise in the first cardiac cycle, and the second set of parameters can include a first height value of the first initial rise in the first cardiac cycle. a second parameter corresponding to a second height value of the second initial rise, the first shape corresponding to the first height value, and the second shape corresponding to the second height value; corresponds to the value of . The first set of parameters may include a first parameter corresponding to a first period of the first initial rise of the first cardiac cycle, and the second set of parameters may include a first parameter corresponding to a first period of the first initial rise of the first cardiac cycle. and a second parameter corresponding to a second period of increase in , wherein the first shape corresponds to the first period and the second shape corresponds to the second period. The first set of parameters can include a first parameter corresponding to a first frequency of the first vibrational component of the first cardiac cycle, and the second set of parameters can include a first frequency of the second vibrational component of the second cardiac cycle. A second parameter corresponding to two frequencies may be included, the first shape corresponding to a first frequency of the first vibrational component and the second shape corresponding to a second frequency of the second vibrational component. The comparison includes comparing a first set of parameters to a second set of parameters and vice versa. To this end, the processor 102 is programmed to determine in real time whether the second set of parameters indicates a predetermined change in the second blood flow waveform relative to the first blood flow waveform, based on the comparison. Can be done.

As disclosed herein, a set (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, Monitoring in real time a person's first blood flow during a first period that includes tens, hundreds, thousands, and any intermediate or entire cardiac cycles of the person (e.g., the integumentary surface, (e.g., head, torso, upper or lower extremities, arms 212, upper arms 214, wrists 216, fingers, toes, thighs, ankles, legs, or any part thereof). ) The processor 102 can be programmed to instruct the worn sensor to generate a first set of readings representing a set of cardiac cycles during a first time period. Similarly, a person (e.g., integumentary surface, bandage, gauze pad, clothing) may be used to monitor the person's second blood flow in real time during a second period that includes a set of cardiac cycles, including the second cardiac cycle. Instructs a sensor that is in contact with or worn by the person (e.g., on the head, torso, upper or lower extremities, arm 212, upper arm 214, wrist 216, finger, toe, thigh, ankle, leg, or any part thereof) The processor 102 can be programmed to cause the sensor to generate a second set of readings representing a set of cardiac cycles during a second time period. The set of cardiac cycles during the first time period and the set of cardiac cycles during the second time period can be continuous or discontinuous, the same or different, and overlapping or non-overlapping. The first cardiac cycle can be included in the second time period, or the second cardiac cycle can be included in the first time period. The first period and the second period can be continuous or discontinuous, and can overlap or not overlap with each other. The first time period and the second time period may be separated from each other by a third time period (eg, an intervening period). The third period is approximately 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, It can be up to 2, or 1 hour, and these times can include any whole or fractional value.

The processor 102 is configured to instruct a sensor worn by the patient to monitor a first blood flow of the patient in real time during a first time period that includes a first cardiac cycle, as disclosed herein. can be programmed such that the sensor generates a first set of readings that cumulatively represent a first cardiac cycle during a first time period as a mathematical function or a result obtained from the mathematical function. . For example, the mathematical function can be a mean value function, median value function, mode function, or other mathematical function. Similarly, the processor 102 can be programmed to instruct a sensor worn by the patient to monitor a second blood flow of the patient in real time during a second time period that includes a second cardiac cycle; The sensor thereby produces a first set of readings that cumulatively represent a second cardiac cycle during a second time period as a mathematical function or a result obtained from a mathematical function. For example, the mathematical function can be a mean value function, median value function, mode function, or other mathematical function. It should be noted that the mathematical functions for the first set of readings and the mathematical functions for the second set of readings can be the same or different mathematical functions.

As disclosed herein, before the second set of readings is generated by the sensor or received by the processor 102, simultaneously with the second set of readings generated by the sensor or received by the processor 102. , or the processor 102 can be programmed to add the first set of readings to the data structure after the second set of readings is generated by the sensor or received by the processor 102. Based on the first data value and the first time value, the first blood flow waveform can be plotted on at least one of a Cartesian plane and an xy plane. Based on the second data value and the second time value, the second blood flow waveform can be plotted on at least one of a Cartesian plane and an xy plane.

As disclosed herein, there can be a system comprising a processor 102 and sensors (eg, blood flow sensor 106, Doppler blood flow sensor 210). The sensor may contact a person (e.g., the person's arm 212, upper arm 214, wrist 216, thigh, ankle, leg, or any part of the person) or may Constructed to be worn (on the ankle, leg, or any other body part). The processor 102 can be programmed to instruct the sensor to monitor the person's blood flow in real time when the sensor is worn by the person (e.g., a blood pressure monitor 108 or other device). ) related to the first blood pressure (or heart rate) measurement. The sensor generates a waveform related to blood flow and sends the waveform to processor 102 . determining whether there is a change in the shape of the waveform indicative of a change in value in the first blood pressure (or heart rate) measurement, the shape change satisfying a predetermined threshold for the patient; programming the processor 102 to obtain a second blood pressure (or heart rate) measurement of the person based on at least one of: a predetermined period of time has elapsed since receiving the blood pressure (or heart rate) measurement; and the second blood pressure measurement is after the first blood pressure measurement.

As disclosed herein, there can be a system that includes a processor 102 that monitors baseline blood flow in a patient during a baseline period that includes a cardiac cycle. , blood flow sensor 106, Doppler blood flow sensor 210), the sensor is programmed to instruct the person (e.g., the person's arm 212, upper arm 214, wrist 216, thigh, ankle, leg, or any body part) to contact or are configured to be worn by a person (e.g., on the person's arm 212, upper arm 214, wrist 216, thigh, ankle, leg, or any location) such that the sensor Generate a set of readings representative of the period. The set of readings represents cardiac cycles during the baseline period. The set of readings relates to blood pressure (or heart rate) measurements (e.g., by sphygmomanometer 108 or other device), and the cardiac cycle is coincident with the baseline blood pressure measurement. After the sensor generates a set of readings, a set of continuous waveform data for non-baseline blood flow is received from the sensor, a parameter change in the set of continuous waveform data is identified, and the parameter change and the baseline programming the processor 102 to calculate a correlation with a line blood pressure (or heart rate) measurement, thereby generating a virtual blood pressure (or heart rate) for non-baseline blood flow, and to perform operations based on the virtual blood pressure; Can be done. For example, this action may be taking a non-baseline blood pressure measurement, or writing something (e.g., writing data, modifying data, erasing data, moving a physical device like a pump, actuator, or motor) or other physical device).

As disclosed herein, there is a system that includes a processor 102, input devices (e.g., blood pressure monitor 108, wearable device, remote device), and sensors (e.g., blood flow sensor 106, Doppler blood flow sensor 210). The sensor may contact the person (e.g., the person's arm 212, upper arm 214, wrist 216, thigh, ankle, leg, or any part of the person) or be connected to the person (e.g., the person's arm 212, upper arm 214, The device is configured to be worn (on the wrist 216, thigh, ankle, leg, or any other location). Processor 102 communicates with input devices and sensors. The processor 102 can be programmed to instruct the sensor to monitor the person's current blood flow when the sensor contacts or is worn by the person, and the current blood flow is input to the person. Associated with current blood pressure measurements received from the device, the sensor thereby generates a waveform associated with current blood flow. As disclosed herein, processor 102 can be programmed to determine whether there is a change in the shape of a waveform indicative of a change in value in a blood pressure (or heart rate) measurement. Processor 102 can be programmed to take action based on the shape change meeting a predetermined threshold for the patient. For example, this action may be taking a non-baseline blood pressure measurement, or writing something (e.g., writing data, modifying data, erasing data, moving a physical device like a pump, actuator, or motor) physical devices, or other physical devices).

to instruct a sensor (e.g., blood flow sensor 106, Doppler blood flow sensor 210) to monitor the patient's baseline blood flow during a baseline period that includes a cardiac cycle, as disclosed herein; There can be a system with a programmed processor 102 that allows the sensor to touch a person (e.g., the person's arm 212, upper arm 214, wrist 216, thigh, ankle, leg, or any part of the person). , configured to be worn by a person (e.g., on the arm 212, upper arm 214, wrist 216, thigh, ankle, leg, or any location) such that the sensor detects a set of cardiac cycles representative of the cardiac cycle during the baseline period. Generates a reading of The set of readings is related to the baseline blood pressure measurement, and the cardiac cycle is either simultaneous with the baseline blood pressure (or heart rate) measurement, occurs at the same time as the baseline blood pressure (or heart rate) measurement, or Immediately preceding the line blood pressure (or heart rate) measurement, immediately following the baseline blood pressure (or heart rate) measurement, or otherwise related to the baseline blood pressure (or heart rate) measurement. As disclosed herein, after the sensor generates the set of readings, a set of continuous waveform data for non-baseline blood flow is received from the sensor, and a parameter in the set of continuous waveform data is received from the sensor. A processor that identifies changes, computes correlations between parameter changes and baseline blood pressure measurements, thereby generating a virtual blood pressure (or heart rate) for non-baseline blood flow, and performs actions based on the virtual blood pressure. 102 can be programmed. For example, this action may be taking a non-baseline blood pressure measurement, or writing something (e.g., writing data, modifying data, erasing data, moving a physical device like a pump, actuator, or motor) physical devices, or other physical devices).

FIG. 4 shows waveform diagrams of specific examples of blood flow waveforms according to FIGS. 1-3 in accordance with various principles of the present invention. Specifically, as disclosed herein, system 100 or system 200 may perform method 300 based on waveform diagram 400. Waveform diagram 400 has an X-axis representing time and a Y-axis representing displacement of the person's blood while the person is wearing the sensor (eg, blood flow sensor 106, Doppler blood flow sensor 210).

In the past, invasive monitoring of blood pressure was typically performed with arterial indwelling catheters that measured blood pressure using a fluid column. Similarly, non-invasive monitoring of blood pressure is commonly performed with frequently repeated measurements using a blood pressure cuff 206 worn on a person's upper arm 214. The blood pressure cuff 206 is inflated to a pressure above the systolic blood pressure expected for a person, and then gradually deflated, while detecting a pulse under pressure within the blood pressure cuff 206 to detect a pressure within some underlying arterial blood vessels. Obtain systolic (maximum) and diastolic (minimum) blood pressure (this method is known as oscillometric method). This process is typically repeated to provide frequent updates, and these frequent repetitions can be felt as uncomfortable by conscious patients and can interfere with relaxation and the ability to fall asleep. To this end, additional blood flow detectors (e.g., continuous wave sensor, blood flow sensor 106, Doppler blood flow sensor 210) may be used within the wristband (or other wearable form factor). or by using the derived physiological blood flow, an additional flow detector generates a blood flow waveform that is used by the processor to generate a virtual blood pressure and estimate the likely blood pressure. Changes can be predicted and therefore blood pressure cuff measurements can be requested only when an indication of a significant change is detected, predicted, expected, or estimated. As disclosed herein, this method significantly reduces the number of required measurements (eg, blood pressure, heart rate) with the blood pressure cuff 206, thus reducing patient discomfort. For example, an upper arm cuff device (eg, blood pressure monitor 108) may initially be used to measure systolic and diastolic blood pressure in arm 212. There is a recording of the blood flow waveform at the person's wrist 216 or other easily monitorable site shortly before or after this measurement (e.g., within about an hour while the person remains at rest). be able to. The blood flow waveform is then continuously monitored and only if a specific change in the blood flow waveform is noticed (e.g., a predetermined or preset change, or meeting or not meeting a certain threshold). Blood pressure is remeasured by blood pressure cuff 206 to restart the monitoring process.

In some embodiments, a battery-powered integrated device ( For example, see FIG. 2). The device may include a sensor (e.g., a blood flow sensor 106) implemented in a band worn over an artery to be detected in a patient, or having other wearable form factors worn or in contact with a person. , a continuous wave ultrasound Doppler blood flow sensor) configured to continuously (or frequently) monitor blood flow in a person's arteries at the same site or at other easily accessible sites; I can do it. As disclosed herein, the device continuously analyzes this blood flow waveform in real time to determine whether a change in waveform shape exists, and the change in waveform shape is determined by blood pressure (or blood pressure). If a significant change is detected or a significant amount of time has elapsed since the last cuff-based measurement, additional blood pressure (or heart rate) measurements with the blood pressure cuff 206 may be performed. , may be configured to instigate or request or command. Note that blood pressure cuff 206 can be worn on upper arm 214 or wrist 216. Similarly, the blood flow sensor can be integrated within the blood pressure cuff 206 or within a separate band (or other wearable form factor) placed on the person's wrist 216, ankle, or thigh. can be implemented in Similarly, by varying the demand for blood flow to the arm 212, independent of any changes in calculated/estimated (virtual) or measured blood pressure, the blood flow waveform in a person's forearm may be A person's femoral artery (e.g., in a person's thigh) can be used to more reliably reflect changes in a person's central blood pressure if it is found to be significantly affected (preset or predetermined). A flow waveform can be provided.

Other embodiments contemplate the simultaneous use of two or more blood flow sensors, such as 106 and 210. These two or more blood flow sensors can be placed in a single location (eg, a sensor array) as in the wearable devices described herein. Instead, these two or more blood flow sensors may be located in different locations such as the head, torso, upper or lower extremities, arm 212, upper arm 214, wrist 216, finger, toe, thigh, ankle, leg, or any portion thereof. It can be placed in any position. The output of each blood flow sensor can be used individually as described above to calculate/estimate multiple virtual blood pressure values. Instead, the outputs of these two or more blood flow sensors are combined using or as a result of a mathematical function, such that the two or more sensors function as an equivalent single sensor; This sensor can be used as described above to calculate/estimate virtual blood pressure values. For example, the mathematical function can be a mean value function, median value function, mode function, maximum value function, minimum value function, weight function, or other mathematical function.

Processor 102 can determine blood pressure changes from changes in blood flow waveform shape in various ways. For example, one such method is to derive one or more parameters of the waveform shape (e.g., Doppler blood flow) for each cardiac cycle and use changes in the one or more parameters to determine whether blood pressure is changing. This can include indicating gender. As shown in FIG. 4, some of these parameters may include the heartbeat period B, the height of the initial rise H, the duration of the initial rise T, the frequency of the oscillatory component 1/C, or others. can.

In one mode of operation, certain assumptions exist, including: (1) the peripheral vascular bed and proximal veins do not change "vascular tone" and the periphery maintains a constant state of perfusion; and (2) the vasculature is linear. Thus, where the vasculature is linear (ie, output responds proportionally to input) and the periphery remains constant, the detected blood flow should vary proportionally to the input blood pressure. This should provide the relationship that blood pressure and blood flow have a linear relationship, so:
・Blood flow from the bottom to the peak is proportional to the blood pressure (pulse pressure) from the lowest to the highest.
- Average blood flow is proportional to average blood pressure.
At first,
Diastolic brachial blood pressure D(0) and systolic brachial blood pressure S(0) are measured.
The lower end F(0) and peak K(0) of a blood flow waveform (for example, a Doppler blood flow waveform) are measured.
The average height M(0) of the blood flow waveform (for example, Doppler blood flow waveform) is measured.
Derive the average blood pressure Pm(0)=(S(0)+2D(0))/3.
Derive the pulse pressure Pp(0)=(S(0)−D(0)).

Next, at a later time (t), the diastolic blood pressure D(t) and the systolic blood pressure S(t) are converted into measured values (for example, Doppler measurements) F(t), K(t), and M( Predict from t):
Pulse pressure: Pp(t)=Pp(0)×(K(t)-F(t))/(K(0)-F(0))
Average blood pressure: Pm(t)=Pm(0)×M(t)/M(0)

This equation can be rearranged to give the following equation:
S(t)=Pm(t)+Pp(t)×2/3
D(t)=Pm(t)-Pp(t)/3
Limitations • Peripheral perfusion can vary independently of blood pressure.
-The arterial system is not linear.
- Mean blood flow (eg Doppler blood flow) cannot be accurately measured for hypopulsatile blood flow.

One mode of operation is to support the validity of these measurements or to replace them with Doppler blood flow waveforms or other waveforms that directly or indirectly represent blood flow. There is a method. It has been observed that when the subject is at rest, the blood flow (velocity) waveform (eg, at the wrist 216, thigh, ankle) typically pulsates strongly. Blood flow (eg, velocity) waveforms have an initial rise following the onset of cardiac contraction, and this rise is the most commonly observed feature of such waveforms. Furthermore, this increase has a height and duration, which vary with blood pressure (although in some cases also with changes in peripheral vascular tone). It is worth investigating the relationship between brachial blood pressure and the resulting peripheral blood flow waveform shape to determine these possible relationships and their relative independence from peripheral vascular conditions.

Suggested parameters include:
・Simple height of rise ・Duration of rise ・Slope of rise Composite waveform shape analysis ・Fitting of the waveform to a simple electrical model driven by the basic driving function
・Time dilation/compression (TDC)
・Laplace modeling

However, it is clear that changing peripheral conditions with unchanged brachial blood pressure can also result in such changes.

Modeling can be used as a method to identify appropriate parameters. Before actually investigating the possible parameters for indicating changes in brachial blood pressure, it is important to examine the known key characteristics of the peripheral vasculature (see Figure 5) to determine whether certain parameters are closely related to driving changes in blood pressure. However, it is useful to check whether it is robust to changes in peripheral conditions.

The simplest model for the drive function shape is: an impulse wave or square wave defined by height and mark/space ratio.

The simplest analogy is the lumped constant circuit shown in FIG. 6, although the actual values of Rs, C, and L will be different from the values in the example shown:
- The mass of blood in a blood vessel can be considered as a constant represented by inductance L.
-Vascular elasticity changes with mean blood pressure and is expressed by capacitance C.
- Vascular resistance can be thought of as a constant expressed by resistance.
- Vascular bed resistance changes depending on peripheral conditions and is also expressed by resistance.

Although it is clear that the elastic compliance of the blood vessel is inversely proportional to log(mean blood pressure), for small changes it can be assumed that the elastic compliance is inversely proportional to the mean blood pressure Pm. Therefore, the elastic compliance of the blood vessel is equivalent to capacitance=1/Pm, whereas the inductance L is constant.

In this circuit, any oscillations produced by the input pulses have frequency = 1/2π×√(LC), which is important because they are not directly influenced by the value of the resistance.

Therefore, assuming that the frequency Fosc(0) is known at a certain mean blood pressure:
Pm(0) Fosc(0)=1/2π×√(L/P(0))

At later time “t”: Fosc(t)=1/2π×√(L/P(t))

Therefore: Pm(t)=Pm(0)×(Fosc(t)/Fosc(0)) ²

Thus, for example, a 5% change in frequency indicates a 10% change in mean blood pressure.

The frequency of vibration can be determined by various complicated procedures, but the time scale from the bottom to the peak of the blood flow waveform (T in Figure 4) is the effective value of the vibration frequency (Fosc, which is proportional to 1/T). This is a simple index, and substitution can be made to simplify the equation using the initial blood flow increase time T(0) and T(t) at a later time.
Therefore: Pm(t)=Pm(0)×(T(0)/T(t)) ²

Using these assumptions, the mean blood pressure at time (t) can be predicted from the initial knowledge of the brachial blood pressure and from the change in vibration frequency or blood flow rise time T of the blood flow waveform supplied to the periphery.

The change in mean blood pressure estimated in this way, Pm(t) - Pm(0), is sufficient as an indicator that the patient's blood pressure has changed and can be used alone as an indicator that a new blood pressure cuff-based measurement is required. It can be used in

More information may exist in the blood flow waveform. Although the above techniques only estimate changes in mean blood pressure, knowledge of systolic and diastolic blood pressure can be considered clinically useful. Since the assumption of linearity is used, the height of the blood pressure waveform change should have a linear relationship with the height change of the blood flow waveform. Therefore, if we consider the systolic increase from Pdias (diastolic blood pressure) to Psys (systolic blood pressure), this increase corresponds to the amplitude swing (fluctuation width) in blood flow measurements from Adias (diastolic amplitude) to Asys (systolic blood pressure). diastolic amplitude) (and for Doppler signals, Vdias (diastolic velocity) to Vsys (systolic velocity), which represents velocity rather than amplitude).

Following the initial measurement at time 0, the proportionality constant K can be derived as:

Furthermore, using a general approximation to mean brachial blood pressure, the three blood pressure parameters can be related as follows.
Pmean=Psys/3+2×Pdias/3

These can be manipulated mathematically to give Psys and Pdias at a future time (t) from the known Psys and Pdias at time (0):
・Assuming that the average blood pressure at time t has already been estimated by the following formula (as above):
Pmean(t)=Pmean(0)×(Fosc(t)/Fosc(0)) ²
・And assuming that K has already been derived:
Psys(t)=Pmean(t)+2×K(Adias(t)−Asys(t))/3
Pdias(t)=Pmean(t)-K(Adias(t)-Asys(t))/3

This allows continuous indication of both systolic and diastolic brachial blood pressure if necessary.

There may be further methods of estimating the frequency of vibration. The shape of the waveform resembles a damped sinusoid and can be estimated by various methods: Fourier analysis, time compression ratio, or most simply by the time required for the initial rise to occur. Since the simplest method using the time from the bottom to the peak of the blood flow waveform has been found to be suboptimal, two further methods are proposed:

Curve Fitting - Time Compression/Stretching Analysis Here, the blood flow waveform for a completed cardiac cycle at time 0 is taken as a reference, and the subsequent blood flow waveform at time t is temporally stretched or compressed by curve fitting. We propose to find a "best fit" with the initial waveform. This can provide a single variable, the Time Compression Ratio (“TCR”), which encompasses only the oscillatory components of the waveform and Unaffected by changes in flow rate. Furthermore, the time compression ratio does reflect the observed waveform frequency variations. For example, the three waveforms in FIG. 8 represent a compressed signal, a normal signal, and an expanded signal.

This compression ratio (TCR = new timescale/original timescale) can then be used instead of the bottom-to-peak time ratio already considered above:
Pm(t)=Pm(0)×(T(0)/T(t)) ² ,
Replace with Pm(t)-Pm(0)/TCR ² .

Curve Fitting - Laplace Transform Modeling Here, two blood flow waveforms are described using the Laplace transform equation based on an impulse drive function that drives a quadratic or cubic Laplace transform function. This process is described in Skidmore R and Woodstock JP (1980), “Ultrasound in Machine & Biology”, V6, pp.7-10. Again, a "best fit" method is employed to obtain appropriate parameters for both waveforms. Next, in estimating the average blood pressure change, a parameter (imaginary part) that affects the frequency of vibration can be used instead of the Fosc ratio.

In a second embodiment, instead of deriving the plurality of parameters from a baseline blood pressure and a baseline waveform associated with the baseline blood pressure, a linear relationship of one or more parameters of the blood flow waveform is derived from at least two It can be determined by examining at least two waveforms acquired at different blood pressures. For example, the area under the waveform curve may be recorded for the current patient's BP (blood pressure), and then for several other incremental (e.g., lower) blood pressures based on that patient's physiology. The speed of BP change can be set. By doing so, this allows the system to minimize the patient's physiological fluctuations when measuring the patient's BP. Furthermore, the area under the curve is averaged over several heartbeats. Other parameters disclosed elsewhere herein can be used in conjunction with or in place of area under the curve.

Once the system is calibrated (by this second method), the patient's BP can be digitally tracked. Then, as with other embodiments, a standard mechanical BP can be performed if a 5, 10, 20% change exists in the digital (or virtual) BP. The threshold for cuff BP checking can be set by the end user. For retail products or outpatient monitoring (ie Holter monitors/pacemakers), these are linked through the application once to several times a day and are again configured by the end user.

Such systems can use linear regression methods to determine mean arterial blood pressure based on the flow velocity of a blood flow waveform (eg, Doppler signal).

A second embodiment calibrates the pulse waveform either with Doppler pulse volume or any waveform that is directly related to blood pressure. The correlation between this waveform and, for example, the maximum amplitude of the patient's systolic BP is calculated, and then the correlation between the average value below the curve and the patient's average BP is calculated. By doing this, we can do this without having to disturb the patient either with invasive arterial catheters that are invasively placed within the patient's peripheral arteries, or with repeated and uncomfortable BP cutting needles. The patient's heart rate, systolic blood pressure, diastolic blood pressure, and mean blood pressure can be continuously tracked in one signal. The overall setup of such a system is shown in FIGS. 2 and 11.

To implement the second embodiment, the BP cuff is inflated and the waveform is recorded throughout. This waveform can be generated from such things as Doppler, plethysmography, or spectrometry. Amplitude, area (average area) and HR (heart rate) were recorded to calculate the correlation with final systolic BP- (cuff blood pressure), thereby determining the [BP and increased BP] and generate a graphical relationship with the waveforms recorded at the same time. This allows calculation of the slope of the line specific to this patient during this period. How often this slope is recalibrated is up to the end user, but may be based on time of day (hourly, every 4, 6, 8, 12 hours), on a daily basis, or based on changes in blood pressure (e.g., 20 mmHg of systolic blood pressure). , a change of 10 mmHg in average blood pressure, a change of 20 mmHg in average blood pressure, and further, for example, a range of SP (systolic pressure)<110 mmHg or SP>180 mmHg).

While the cuff is inflated, the amplitude, HR, and area under the curve are recorded and stored for each beat. The user or manufacturer can set the number of data to be collected. This is done until the patient's actual BP reaches a state where the waveform is known to go to zero. However, only two points are required to determine the slope of the patient's waveform parameters. A larger number of points only improves these measurements. Furthermore, although this process does not necessarily have to track increases or decreases in cuff pressure from the outside, performing this process is in some ways dependent on the context of the measurements. There may be some benefit to other processes. The key is to obtain waveforms at at least two BPs. Furthermore, applying external pressure with the cuff is one way, but not the only way, to ensure that the waveform is captured at more than one BP point. An application or other software-driven accomplisher can be used to instruct a patient to perform two or more actions, ensuring that the resulting BP between these actions is likely to be different. Waveforms are captured at the completion of these actions, or during these actions, and although the actual BP is not known, a linear relationship of the patient's BP will be calculated. Figure 9 shows a set of such measurements. As shown in FIG. 9, elevated blood pressure BP _A is best calculated by dilation before vasodilation occurs due to downstream isolation. To collect data, cuff blood pressure measurements can be automated with a system that records at set, predetermined intervals. Measured blood pressure (systolic BP) - cuff blood pressure is expressed as SBP _M. Average value under the curve - (minus) Average value of the area under the curve. Diastolic BP is calculated as 11/2 MAP _WF - SBP _WF . The relationship between MAP (mean arterial pressure), MAP _A , SBP _A , and DBP _A is provided by the following equation:
(SBP: systolic blood pressure, DBP: diastolic blood pressure).

Other embodiments consider the pulsatile nature of the blood flow waveform. Pulse generation is based on the principle that when the ventricle contracts to create the necessary pressure gradient, a large volume of blood is rapidly ejected into the arterial vessels. Aortas and arteries have lower resistance to blood flow compared to arterioles and capillaries. During diastole, the elastic contractile forces of the arteries force blood into the arterioles.

The resistance coefficient is a measure of pulsatile blood flow that reflects the resistance to blood flow created by the microvascular bed distal to the site of measurement. RI (resistance index) is generally measured by Doppler sonography in the renal arteries and is calculated by the following formula:

A normal RI is about 0.7 for adults. An RI of 1 indicates systolic blood flow without diastolic flow, and an RI greater than 1 indicates regurgitation of diastolic blood flow.

Pulsatility index (PI) velocity, also known as Gosling coefficient, can be generated from a waveform. PI is calculated from the pulse Doppler waveform using Equation 3 below.

PI, also known as retrograde/forward flow coefficient, indicates the pulsatile amplification (V _max −V _min ) and the stiffness of the artery. Systolic blood pressure is approximately equal to the amplification of the beat minus (minus) the amplitude of the beat.

In the methods and systems of the present invention, MAP can be determined based on AUC (area under the curve) or "work". Work is force over a distance, and force is mass times acceleration. In a preferred embodiment, the force curve is a Doppler waveform; the mass is blood that has both forward and reverse motion. Blood pressure is a force represented by the slope of the waveform from moment to moment. Amplitude represents the mass or volume of blood; distance is the visible spectrum of the probe. The amount of work is the sum of the AUCs of the waveforms.

In a preferred embodiment, the baseline mean arterial pressure is calculated with the simplified (modified) Bernoulli equation, where P is the blood pressure, V ₁ is the velocity before the orifice, and V ₂ is the velocity after the orifice. The speed is

The Bernoulli equation is an energy conservation principle suitable for flowing fluids such as blood. The "Bernoulli effect" is a region where fluid pressure decreases, where flow velocity increases. In a preferred embodiment, blood pressure is calculated from the Bernoulli equation when the diameter of the tube or blood vessel is known.

Figure 9 shows the linear regression of systolic blood pressure (SBP) against pulsatile amplification (V _max - V _min ), except that the horizontal axis is the amplitude of (V _max - V _min ) instead of the "waveform" amplitude. be. In this embodiment, the fitted (approximated) patient's blood pressure is the slope of linear regression. As mentioned above, the Bernoulli equation assumes that the fitted patient's blood pressure should remain constant. The system and method according to the invention therefore detects this change in slope. Using pulsatility coefficient may provide more benefits in critically ill patients. V _ff - pulsatility coefficient velocity or (V _max - V _min )/V _mean and systolic BP ~ (V _max - V _min ) - pulsation amplitude.

In this embodiment, MAP is related to (V _max −V _min )/V _mean instead of the average area under the curve. Then, the calculation related to Figure 9 is as follows:

Once a linear relationship (ie, a patient-specific relationship) is established for a patient, continuous blood pressure monitoring can be performed. This can be done by personal use, for example by using wristbands, finger clips, ear clips that interface with smart devices (phone tablets/computers) that have a processor via Bluetooth®. This smart device can store data locally (within the device) or on the cloud. See Figure 10. For ambulatory medical applications where a patient's BP is tracked while the patient performs daily activities, this can be applied to Holters, pacemakers, cardiac monitors, cardiac electrical stimulators, and implantable cardiac defibrillators (ICDs). (defibrillator) via a finger clip, ear clip, or wristband, for example by Bluetooth®. and for medical/clinical care, wristbands, finger clips, ear clips, etc. that interface with monitoring systems linked to the patient's medical record by Bluetooth® (or other communication protocols). Equipped with continuous digital vital signs monitoring equipment, etc.

In a third embodiment, no baseline or calibration BP measurements are performed. That is, there is no externally applied pressure or application instructing the user to perform an action, thus artificially exploiting or raising/lowering the user's BP. Instead, the assumed common BP waveform mapping is used to enable calculation of virtual BP. More data from a larger population of users helps establish a more robust map. In use, the actual or measured BP may not be known at all, but such BP can be easily calculated from the monitored waveform. Instead, the method of the third embodiment relies on monitoring waveform parameter changes based on a general BP waveform mapping.

Various techniques for monitoring blood pressure can be used to predict, diagnose, monitor, or treat medical conditions, diseases, or illnesses in humans, animals, pets, fish, or birds, including fetal, postnatal, neonatal, Infants, toddlers, preschoolers, children, teens, adults, older adults, paralyzed, wheelchair-bound, or otherwise non-dependent. For example, some medical conditions, diseases, or diseases include arthritis, low and high blood pressure, asthma, cancer (e.g., lung cancer, bronchial cancer, prostate cancer, colon cancer, rectal cancer, breast cancer, liver cancer, pancreatic cancer, gallbladder cancer, bladder cancer, uterine cancer, kidney cancer, leukemia, melanoma, non-Hodgkin's lymphoma, thyroid cancer, or other cancers), diabetes (e.g., type 1, type 2), bronchitis, coronary artery disease Heart disease, dementia, Parkinson's disease, Alzheimer's disease, epilepsy, multiple sclerosis, osteoporosis, stroke, heart attack, chronic kidney disease, deep vein thrombosis, shingles, acne, anxiety, sleep apnea disease, atherosclerosis, nephritis, nephritic syndrome, skin burns, nephrosis, gallstones, jaundice, cirrhosis, indigestion, stomach ulcers, infections (e.g., influenza or others), spinal curvature, spondylosis, spinal stenosis, fractures. , ischemic heart disease, or others.

It should be understood that the above description is intended to be illustrative rather than restrictive. For example, the embodiments (and/or aspects thereof) described above can be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the subject matter without departing from the scope of the embodiments. While dimensions or materials described herein are intended to define the parameters of the subject matter, they are in no way limiting, but are preferred embodiments. Many other embodiments will be apparent to those of ordinary skill in the art upon reviewing the above description. The scope of the subject matter described herein should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, "comprising" and "in" are used as the plain-text equivalents of "comprising" and "herein," respectively. Furthermore, in the following claims, "first," "second," "third," etc. are used merely as labels, and are not intended to impose numerical requirements on these objects. Further, the following claim limitations are not written in a means plus function format, and such claim limitations may be interpreted as "for (...)" followed by a functional statement without further structure. Unless and until "means" is explicitly used, 35U. S. C. §112, 6th paragraph.

This specification uses examples to disclose several embodiments of the subject matter, including the best mode, and to enable any person of ordinary skill in the art to understand and understand the embodiments disclosed herein, by any device or system. It also enables one to make and use and practice, including performing, any method contained herein. The patentable scope of the subject matter is defined by the claims, and may include other examples that occur to those of ordinary skill in the art. These other examples fall within the scope of the claims if they have structural elements that do not differ from the language of the claims, or if they include equivalent structural elements that do not materially differ from the language of the claims. is intended to be.

The foregoing description of specific embodiments of the disclosed subject matter is better understood when read in conjunction with the accompanying drawings. To the extent that the drawings depict diagrams of functional blocks of various embodiments, these functional blocks do not necessarily indicate a division between hardware circuits. Thus, for example, one or more of the functional blocks (e.g., a processor or a memory) may be realized in the form of a single piece of hardware (e.g., a general-purpose signal processor, a microcontroller, a random access memory, a hard disk, etc.). can. Similarly, the above programs can be standalone programs, included as subroutines within the operating system, functions within installed software packages, etc. . These various embodiments are not limited to the configuration and instrumentality shown in the drawings.

As used herein, the use of an element or step in the singular and preceded by "an" or the like shall be understood as not excluding a plurality of such elements or steps, unless such exclusion is expressly stated. Should. Furthermore, references to "one embodiment" of the present subject matter are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Furthermore, unless expressly stated to the contrary, an embodiment that "comprises," "includes," or "has" an element or elements having a particular property does not include such elements not having that property. can additionally be included.

Since certain changes may be made in the systems and methods described above without departing from the spirit and scope of the subject matter contained herein, all of the subject matter described above or illustrated in the accompanying drawings is incorporated herein by reference. shall be construed merely as an illustrative example of the concepts herein and shall not be construed as limiting the disclosed subject matter.

Various embodiments of the invention may be implemented in a data processing system suitable for storing and/or executing program code, including at least one processor coupled directly or indirectly to memory elements through a system bus. can do. These memory elements include, for example, local memory used during the actual execution of the program code, and cache memory that provides temporary storage of at least some program code to retrieve the code from mass storage during execution. reduce the number of times you have to

I/O (input/output) devices (keyboards, displays, pointing devices, DASDs (direct access storage devices), tapes, CDs (compact discs), DVDs (digital versatile discs) (including but not limited to general purpose disks), thumb devices, thumb drives (a type of USB flash memory), and other storage media), either directly or through intervening I/O controllers, into the system. can be combined with Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or to remote printers or remote storage devices through intervening facilities or public networks. Modems, cable modems, and Ethernet cards are just a few of the types of network adapters available.

The invention may be implemented in a system, method, and/or computer program product. The computer program product may include a computer readable storage medium having computer readable program instructions for causing a processor to perform aspects of the invention on the computer readable storage medium. The computer-readable storage medium may be a tangible device that can retain and store instructions for use by an instruction execution device. The computer-readable storage medium can be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the above. This non-exclusive list of more specific examples of computer readable storage media includes: portable computer diskettes, hard disks, random access memory (RAM), read only memory. (ROM: read-only memory), erasable programmable read-only memory (EPROM), static random access memory (SRAM), portable compact disk read-only memory (CD- mechanically encoded devices such as ROM), digital versatile disks (DVDs), memory sticks, floppy disks, punched cards, or textured structures with instructions recorded in grooves, and any of the above. The right combination.

The computer readable program instructions described herein may be transferred from a computer readable storage medium to a respective computing/processing device or over a network, such as the Internet, a local area network, a wide area network, and/or a wireless network. Can be downloaded to an external computer or external storage device. This network can include copper transmission cables, optical transmission fibers, wireless transmissions, routers, firewalls, switches, gateway computers, and/or edge servers. A network adapter card or network interface within each computing/processing unit receives computer-readable program instructions from the network and transfers the computer-readable program instructions to a computer-readable storage medium within the respective computing/processing unit. Transfer to for storage.

Computer-readable program instructions for carrying out the operations of the present invention include assembler instructions, instruction set architecture (ISA) instructions, machine language instructions, machine-dependent instructions, microcode, It can be firmware instructions, state configuration data, or source code or object code written in any combination of one or more programming languages, such as object-oriented programming such as Smalltalk, C++, etc. languages, and traditional procedural programming languages, such as the "C" programming language or similar programming languages. A code segment or machine-executable instructions may represent a procedure, function, subprogram, routine, subroutine, module, software package, class, or any combination of instructions, data structures, or program statements. Code segments can be coupled to other code segments or hardware circuits by passing and/or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, etc. may be passed, transferred, or transmitted by any suitable means, including memory sharing, message passing, tokens, etc. including delivery and network transmission. The computer-readable program instructions may be provided entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer, and partially on a remote computer, or The entire thing can be run on a remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or wide area network (WAN), or , this connection can be made to an external computer (eg, through the Internet using an Internet service provider). In some embodiments, electronic circuits, including, for example, programmable logic circuits, field programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), can be programmed with a computer-readable program. Computer readable program instructions can be executed to carry out aspects of the present invention by personalizing electronic circuitry using the instruction state information.

Aspects of the invention are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It is understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer readable program instructions. The various example logic blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or a combination of both. can. To clearly explain the compatibility of such hardware and software, various example components, blocks, modules, circuits, and steps have been described above generally in terms of functionality. Whether such functionality is implemented as hardware or software depends on the specific application and design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in various ways for each specific application, and such implementation decisions should not be construed as resulting in a departure from the scope of the invention.

The flowcharts and block diagrams in the drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the invention. In this relationship, each block in a flowchart or block diagram can represent a module, segment, or part of a set of instructions that can be used to implement one or more executable instructions for implementing the specified logical function. Contains instructions. In some alternative implementations, the functions noted within the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may actually be executed substantially simultaneously or the blocks may sometimes be executed in the reverse order, depending on the functionality involved. Additionally, each block in the block diagrams and/or flowchart diagrams, and combinations of blocks in the block diagrams and/or flowchart diagrams, represent specific combinations of hardware and computer instructions that perform specified functions or operations. can be realized by a special-purpose hardware-based system that performs the

Words such as "and" and "next" are not intended to limit the order of steps; they are only used to guide the reader through the description of the method. Although a process flow diagram may describe the operations as a sequential process, many of the operations can be performed in parallel or simultaneously. Additionally, the order of operations can be rearranged. A process may correspond to a method, function, procedure, subroutine, subprogram, etc. When a process corresponds to a function, its termination may correspond to a return from this function to the calling function or to the main function.

Features or functionality described with respect to particular embodiments may be incorporated within and/or subcombined with various other embodiments. Also, different aspects and/or elements of the embodiments disclosed herein may be combined and subcombined in similar manners. Furthermore, some embodiments may be components of a larger system, either individually or collectively, in which other procedures may take precedence over the application of these embodiments and/or , may otherwise modify the application of these embodiments. Additionally, multiple steps may be required before, after, and/or concurrently with the embodiments disclosed herein. It is noted that at least any and/or all of the methods and/or processes disclosed herein may be performed, at least in part, by at least one entity or operator in any manner.

Although the preferred embodiments have been illustrated and described in detail herein, those skilled in the art will recognize that various modifications, additions, substitutions, etc. can be made without departing from the spirit of the invention. It's a place. They are therefore considered to be within the scope of the invention as defined in the following claims.

Claims (24)

a processor to instruct a sensor worn by a subject to monitor a first blood flow of the subject during a period of time that includes a cardiac cycle of the subject, thereby causing the sensor to monitor a first blood flow of the subject during a period of time that includes a cardiac cycle of the subject; generating a first set of waveform data representative of a period, the first set of waveform data being associated with a blood pressure measurement;
receiving, by the processor, a second set of waveform data in a second blood flow from the sensor after the first set of waveform data is generated by the sensor;
identifying, by the processor, a parameter change in the second set of waveform data relative to the first set of waveform data;
calculating, by the processor, a correlation between the parameter change and the blood pressure measurement, thereby generating a virtual blood pressure for the second blood flow;
performing an action by the processor based on the virtual blood pressure. 2. The method of claim 1, wherein the blood pressure measurement is a first blood pressure measurement, and the act includes instructing the blood pressure monitoring device to obtain a second blood pressure measurement different from the first blood pressure measurement. Method described. 3. The method of claim 2, wherein the processor directs the blood pressure monitoring device to obtain the first blood pressure measurement. 2. The method of claim 1, wherein the parameter change is a change in waveform shape. 2. The method of claim 1, wherein the sensor is a continuous wave sensor. The subject has a finger, toe, wrist, ankle, or thigh, and the continuous wave sensor is worn on at least one of the subject's finger, toe, wrist, ankle, or thigh. 6. The method according to claim 5. 6. The method of claim 5, wherein the subject wears a blood pressure cuff that enables blood pressure measurements, and the blood pressure cuff includes the sensor. The processor derives a first parameter of a first waveform shape for each cardiac cycle during the first blood flow period, and derives a second parameter of a second waveform shape for each cardiac cycle during the second blood flow period. 2. The method of claim 1, identifying the parameter change based on deriving the first parameter and identifying the change between the first parameter and the second parameter. 9. The method of claim 8, wherein each of the first parameter and the second parameter is a heartbeat cycle. 9. The method of claim 8, wherein each of the first parameter and the second parameter is an initial rise height. 9. The method of claim 8, wherein each of the first parameter and the second parameter is a period of initial rise. 9. The method of claim 8, wherein each of the first parameter and the second parameter is a frequency of a vibrational component. A device comprising a processor, the processor comprising:
instructing a sensor worn by a subject to monitor a first blood flow of the subject during a time period that includes a cardiac cycle of the subject, such that the sensor is representative of the cardiac cycle during the time period; generating a first set of waveform data, the first set of waveform data being associated with a blood pressure measurement;
receiving a second set of waveform data in a second blood flow from the sensor after the first set of waveform data is generated by the sensor;
identifying a parameter change in the second set of waveform data relative to the first set of waveform data;
calculating a correlation between the parameter change and the blood pressure measurement, thereby generating a virtual blood pressure for the second blood flow;
A device programmed to perform actions based on said virtual blood pressure. 14. The blood pressure measurement of claim 13, wherein the blood pressure measurement is a first blood pressure measurement, and the act includes instructing the blood pressure monitoring device to obtain a second blood pressure measurement different from the first blood pressure measurement. The device described. 14. The apparatus of claim 13, wherein the parameter change is a change in waveform shape. 14. The apparatus of claim 13, wherein the sensor is a continuous wave sensor. 17. The apparatus of claim 16, wherein the subject wears a blood pressure cuff that enables blood pressure measurements, the blood pressure cuff including the sensor. The processor derives a first parameter of a first waveform shape for each cardiac cycle during the first blood flow period, and derives a second parameter of a second waveform shape for each cardiac cycle during the second blood flow period. 14. The apparatus of claim 13, wherein the parameter change is identified based on deriving the first parameter and identifying the change between the first parameter and the second parameter. 19. The apparatus of claim 18, wherein each of the first parameter and the second parameter is a heartbeat cycle. 19. The apparatus of claim 18, wherein each of the first parameter and the second parameter is an initial rise height. 19. The apparatus of claim 18, wherein each of the first parameter and the second parameter is a period of initial rise. 19. The apparatus of claim 18, wherein each of the first parameter and the second parameter is a frequency of a vibrational component. 2. The method according to claim 1, wherein the operation includes instructing an output device to output the virtual blood pressure or the virtual heartbeat, or instructing a transmitter to transmit the virtual blood pressure or the virtual heartbeat. Method. 14. The operation of claim 13, wherein the operation includes instructing an output device to output the virtual blood pressure or the virtual heartbeat, or instructing a transmitter to transmit the virtual blood pressure or the virtual heartbeat. Device.

Images